Reserved polyamide fibers and a



Patented Dec. 30, 1952 RESERVED POLYAMIDE FIBERS AND A PROCESS FORDYEING THE SAME Otto Fuchs, Basel, Switzerland, assignor to J. R. GeigyA. G., Basel, Switzerland, a Swiss firm N Drawing. Application February27, 1950, Se-

rial No. 146,637. In Switzerland February 3,

4 Claims.

The present invention concerns a dyeing process for textiles made upfrom synthetic polyamide fibres and other textile fibres and also thedyed material obtained according to the new process. In particular it isconcerned with the reservation of the synthetic undyed or pre-dyed partof the fibres when dyeing mixed textiles made up of synthetic polyamidefibres and natural protein fibres with acid wool and chrome dyestuffs.

Mixed spun yarns and mixed weaves made up from natural textile fibresand synthetic polyamide fibres and the textiles made up therefrom enjoyan ever increasing popularity because they combine the provedproper-ties of the natural fibre, e. g. the heat insulating propertiesof the wool which the artificial product has not yet attained, with theimproved physical properties of the synthetic polyamide fibres, e. g.the improved tensile strength. Also, processes gain in importance whichare concerned with the dyeing of such mixed textile fibres.

By the expression synthetic polyamide fibres are meant those highmolecular artificial products which arise from organic bifunctionalamino-, hydroxy", carboxyl-, amino-hydroxy-, and carbonyl compounds byamide-like linkage, which have also been called synthetic proteinfibres, linear-polymeric amides, superpolyamides, superpolyurethanes orsynthetic polyamides and which today are known in the textile industryunder partly registered names such as Nylon or Perlon. Because of thesimilar chemical construction, these artificial fibres behave in asimilar manner to wool on dyeing, and can be dyed with typical wool andchrome dyestuffs from an acid aqueous dye liquor. However, according totheir chemical composition, physical condition and type of technicalproduction, they show decided diiierences to a greater or lesser degree.Generally, with good afi'inity, the saturation point for W001 dyestuffsis different from that for natural fibres so that components ofsynthetic fibres are dyed to varying depths. For this reason, theproblem of the level dyeing of mixed textiles made up from wool andsynthetic polyamide fibres is very difficult to solve. Also according toconstitution and number of sulphonic acid groups, the wool dyestuffsshow considerable differences in aflinity. A process is now known inwhich organic sulphonic and carboxylic acids having afilnity for theartificial fibre and therefore partly reserving them, are made to act onthe synthetic fibre component before or during dyeing with the wooldyestufi, whereby a more level dyeing of mixed fabrics is attained. Astrials have shown, however, a true white reservation of the undyedartificial fibres has not been attained by the above agents in the usualconcentrations.

In contrast to this, it has now been found that according to the usualdyeing methods, the synthetic fibre component can be largely, if notcompletely, reserved when dyeing mixed material made up from natural andsynthetic protein fibres with wool dyestuiis, in which :process also anafter-treatment with suitable chrome dyestuffs is understood. This canbe done by subjecting the synthetic fibre component, either before orduring dyeing, alone or with the natural fibre component, in a weaklyacid, preferably organic acid, medium to the action of synthetic tanningagents of the naphthalene monosulphonic acid, dihydroxydiphenyl sulphoneand formaldehyde condensation product classes. According to the newprocess it is possible, for example, to obtain wool dyeings with purewhite or coloured effect threads of syn-thetic polyamide fibres.

By the expression natural protein fibre silk, preferably wool, and bysynthetic protein fibres the artificial fibres described above aremeant. The condensation products used according to the above inventionare already known as synthetic tanning agents. They are obtained bycondensation of naphthalene monosulphonic acids (preferablyZ-naphthalene sulphonic acid or its admixture with l-naphthalenesulphonic acid), and 4.4 dihydroxydiphenyl sulphones (which can also besubstituted in the phenyl radicals if required, but if so preferablymethyl substituted), with formaldehyde in an aqueous acid medium byapplication of a molecular ratio of l:0.'7-1.5:0.7-1. Surprisingly, ithas been shown that, from among the synthetic tanning agents which aremostly sulphonic acids of formaldehyde condensation products of aromatichydroxyl compounds, just those condensation products applied accordingto the invention are excellent because of a particularly markedreservation action on synthetic polyamide fibres. Even in the usualamounts of a few per cent, calculated on the weight of fibres to betreated, a very good if not complete white reservation of the undyedsynthetic polyamide fibres, and a very pure shot effect on dyeingpre-dyed synthetic polyamide fibres mixed with wool with wool dyestuiisis obtained. The reserving agents according to this invention are bestused for reserving synthetic polyamide fibres alone in a weakly acid, e.g. acetic or formic acid, dyebath after which the artificial fibres arespun or woven with the natural fibres. It is also possible to subjectfinished mixed spun or woven fabrics to a pretreatment with thereserving agents according to this invention in a weakly acid medium,rinse well and then dye with acid wool dyestuffs. Finally, the reservingagents according to this invention can also be added direct to thedyebath with the acid wool dyestuff and the goods dyed in the usualmanner. If possible, the first method is to be preferred to the othersto attain the best possible reservation because it can be easilycontrolled.

The choice of suitable dyestuffs also plays a part in the dyeing processaccording to this invention, because as already mentioned above, thechemical constitution and number of sulphonic acid groups of the wooldyestuff influences the affinity for synthetic polyamide fibres. As arule it can be said that in the process according to this inventionsimply constructed dyestuffs are generally more suitable thancomplicated ones, i. e. monoazo dyestuffs are better than polyazodyestuffs and the dyestuff with more sulphonic acid groups generallygives better effects than monosulphonic acids. However, there are verysuitable dyestuffs available in all the most known classes of wooldyestuffs, for instance, among the acid anthraquinone, acidtriphenylmethane, azo and azochrome wool dyestuffs. According to thepresent invention mixed textile fabrics made up of synthetic and naturalprotein fibres are dyed with wool dyestuffs according to the usualmethods by heating in an acid, preferably an organic acid, dyebathcontaining Glaubers salt. Chrome dyestuffs can be converted into themetal complex in the usual way by treatment with chrome salts. On theother hand those prepared chrome complexes of azochrome dyestuffs whichneed a strong mineralacid dyeing process are less suitable for theprocess according to this invention. On dyeing mixed fabrics made up ofsynthetic polyamide fibres and cellulose fibres with direct dyestuffs, acertain reservation is attained by the synthetic tanning agents usedaccording to this invention, however not nearly so good effects areattained as by the process claimed according to this invention.

The following examples illustrate the dyeing process according to thisinvention without limiting it in any way. Parts are given as parts byweight and temperatures in degrees Centigrade.

A. RESERVATION OF THE FIBRES Example 1 (a) Nylon fibres in the skein arekept moving for half an hour at boiling temperature in an aqueoustreatment bath (liquor ratio 1:30) which contains 3% of a synthetictanning agent calculated on the weight of the fibres, consisting of acidcondensed resin from 1 mol of a technical mixture of about 85%naphthalene-Z- and about naphthalene-1-sulphonic acid, 1 mol 4.4-dihydroxy-diphenyl sulphone and 1 mol formaldehyde, and 3% formic acid.The fibres are then well rinsed and dried. The fibres so prepared areincorporated as effect threads in undyed woollen fabric and then dyed asdescribed in the following examples.

(1)) The same procedure as under (a) is followed, but a synthetictanning agent consisting of acid condensed resin from 1 mol of thetechnical mixture of about 85% naphthalene-Z- and about 15%naphthalene-l-sulphonic acid, 1.5 mol lei dihydroxy-diphenyl sulphoneand 1 mol formaldehyde is used.

(c) The same procedure as under (a) is followed, but a synthetic tanningagent consisting of acid condensed resin from 1 mol of the technicalmixture of about 85% naphthalene-Z- and ca. 15% naphthalene-l-sulphonicacid, 0.7 mol 4. idihydroxy-diphenyl sulphone and 0.75 mol offormaldehyde is used.

(at) The same procedure as under (a) is followed but a synthetic tanningagent prepared from 1 mol naphthalene-Z-sulphonic acid, 1 mol4.4-dihydroxydiphenyl sulphone and 1 mol formaldehyde is used.

Example 2 Perlon L, a polyamide fibre produced from the polymerisationproduct of e-aminocaprolactam is reserved with a synthetic tanning agentaccording to the process described in Examples la-d.

Example 3 Perlon U, a synthetic fibre produced from polyurethane isreserved with a synthetic tanning agent according to the processdescribed in Examples la-d.

Example 4.-Res-eroation of mic-red fabrics- A union consisting of 50%wool and 50% nylon is boiled for half an hour in an aqueous treatmentbath which contains 2% of a synthetic tanning agent as described inExamples la-d calculated on the total fibre mixture, and 3% formic acidin a liquor ratio of 1:30. It is then well rinsed and finally dyed asdescribed in Example 13.

B. DYEING WITH ACID AZO DYESTUFFS Example 5 A piece of wool flannelwhich contains a nylon effect thread reserved according to Example 1a isdyed for an hour at boiling temperature in a dyebath (liquor ratio1:50), which containsl0% of the weight of the fibres of Glaubers salt,2% of the dyestuif from diazotised l-aminonaphthalene coupled with2-hydroxynaphthalene-6,8- disulphonic acid=Krystallponceau 6B (Schultz,Dyestufi Tables, VII, Edition, No. 126) and 5% formic acid. It is thenwell rinsed and dried. .A red wool dyeing is obtained with a pure whitenylon effect.

Very similar dyeings of wool flannel with'nylon effect threads areobtained, the effect threads having been reserved with similar synthetictanning agents according to Examples lb-d or with Perlon U effectthreads which have been reserved with various synthetic tanning agentsaccording to Example 3.

If, in the above example, a dyestuff from diazotised 4-acetamino-l-aminobenzene coupled with l-amino 8 hydroxynaphthalene 3.6 disulphonic acidAmidonaphthol red 6B (Schultz, VII, No. is used, bluish-red wool dyeingswith white nylon or Perlon effects are obtained.

Example 6 A piece of wool flannel with Perlon L effect threads reservedaccording to Example 215 dyed at the boil for three quarters of an hourin a dyebath (liquor ratio 1:30) which contains 10% Glaubers saltcalculated on the weight of the fibers, 4% formic acid and 2% of themonazo dyestuff from diazotisedl-amino-S-hydroxynaphthalene-3.fi-disulphonic acid coupled with 1-phenylamino-naphthalene 8 sulphonic acid: Sulphone Acid Blue R (Igfa). Areddish-blue wool dyeing with white Perlon L effects is obtained.

Similar good white effects are obtained with nylon or Perlon U fibresreserved according to Examples 1a-d or Example 3.

If, in the above example, a dyestufi" .from diazotised1-aminonaphtha1ene-4-sulphonic acid coupled with2-hydroxynaphthalene-3.G-disulphonic acid=Azorubin S (Schultz, VII, -No.212) is used, bluish-red wool dyeings with white polyamide threadeffects are obtained.

Example 7 White wool flannel with nylon effect threads reservedaccording to Example 1 is dyed at the boil for an hour in a dyebath(liquor ratio 1:30) which contains 10% Glaubers salt calculated on theweight of the fibres, 3% formic acid and 2% of the diazo dyestuff fromdiazotised aminoazo benzene monosulphonic acid coupled with 2-hydroxynaphthalene 6 sulphonic acid=Wool Fast Scarlet R (Schultz VII,No. 565). A red dyeing is obtained with good white effect threads. If,in the above example, a dyestuif from diazotised aniline coupled with1-aminonaphthalene-B-sulphonic acid diazotised and coupled withl-phenylamino-naphthalene-8-sulphonic acid: Sulphone Cyanine R (SchultzVII, No. 552) is used, a deep blue wool dyeing with white nylon effectthreads is obtained.

C. DYEING WITH CHROME AZO DYESTUFFS Example 8 Undyed wool flannel withPerlon L effect threads reserved according to Example 2 is dyed for 45minutes at the boil in a dyebath (liquor ratio 1 :30) containingGlaubers salt, 3% formic acid and 2% of the chrome azo dyestuff fromdiazotised 2-amino-4-sulpho-3'-carboxy-4'- hydroxydiphenyl sulphonecoupled with Z-amino- 8-hydroxynaphthalene 6 sulphonic acidzDiamond Red3B (Igfa). It is then rinsed and chromed at the boil for half an hour ina fresh bath containing 3% formic acid, 10% Glaubers salt and 1.5%bichromate. A bluish-red wool dyeing is obtained with only faintlyyellowishwhite effect threads.

A similar result is obtained with Perlon U effect threads.

A yellow dyeing with white effect threads can be obtained if, in theabove example, a dyestuff from diazotised Z-aminobenzene 1 sulphonicacid coupled with 1 [2' (3" carboxy 4" hydroxyphenylsulphonyl)-5'-sulphonic acidl-3- methyl-5-pyrazolonezAcid Chrome YellowBGL (Stturechromgelb 3GL) is used. 7

Example 9 W001 flannel with nylon effect threads reserved according toExample 1 is dyed for 45 minutes at the boil in a dyebath (liquor ratio1:30) containing 2% of a chrome dyestuff from diazotised 4-chloro-2-aminophenol coupled with 1.8-dihydroxynaphthalene 3.6disulphonic acidzFast Mordant Blue B (Igfa), 10% Glaubers salt and 3%formic acid, and then chromed in a fresh bath containing 3% formic acid,10% Glaubers salt and 1.5% bichromate for half an hour at the boil. Ablue dyeing with pure white nylon effects is obtained. White effectswill also be obtained with Perlon U fibres mordanted according toExample 3.

A violet dyeing with white Perlon U or nylon effects can be obtained if,in the above example 2% of a dyestuff from diazotised 4-ch1oro-2-aminophenol-S-sulphonic acid coupled with 1- hydroxynaphthalene 5sulphonic acid Acid Chrome Blue 2R (Saurechromblau 2B) is used.

Example 10 Wool flannel with nylon effect threads reserved according toExample 1 is dyed for half an hour at the boil in a dyebath (liquorratio 1:30) containing 10% Glaubers salt calculated on the weight of thefibres, 3% formic acid and 2% of the chrome azo dyestulf from diazotised4- chloro-2-aminophenyl-6-sulphonic acid coupled with1-hydroxynaphthalene-4-sulphonic acid: Acid Chrome Blue 5R (Igfa)(saurechromblau 5R4). The dyeing so obtained is then chromed for half anhour at the boil in a fresh bath containing 3% formic acid and 1.5%bichromate. A violet dyeing with white effects is obtained.

A green dyeing with white effects is obtained according to the aboveprocess when a dyestuff from diazotised 5-nitro-2-aminophenol coupledwith 1-amino-8-hydroxynaphthalene-3.6-disu1- phonic acid:EriochromeGreen H (SchultzVII, No. is used.

D. DYEINGS WITH ACID WOOL DYESTUFFS OF OTHER- CLASSES Example 11 Woolflannel with white nylon effect threads reserved according to Example 1,is dyed at the boil for an hour in a dyebath (liquor ratio 1:30)containing 10% Glaubers salt calculated on the weight of the fibre, 45%formic acid and 2% 1.5-dihydroxy 4.8 diamino-anthraquinone-2.6-disulphonic acid Alizarine Saphirol B (Schultz VII, No. 1187). A bluedyeing with white effects is obtained. Similar effects are obtained withPerlon U fibre mordanted according to Example 3.

Example 12 E. DYEING OF RESERVED MIXED FABRICS Example 13 A union fabricof 50% nylon and 50 wool pretreated according to Example 4 is dyed in adye bath (liquor ratio 1:30) containing 10% Glaubers salt calculated onthe weight of the fibres, 3% formic acid and 2% dyestuff. White nyloneffects are obtained. A

Dystuff Effects Azo rubine S (Schultz VII, No. 212) red t hitc.Afigonaphthol rod 613 (Schultz VII, No. blue-red... Do.

Example 14.-Reseroation and dyeing in the same bath A dyebath isprepared containing 10% Glaubers salt calculated on the weight of thefibres, 1.5% of a synthetic tanning agent from 1 molnaphthalene-Z-sulphonic acid, 1 mol 4.4'-dihydroxydiphenyl sulphone and1 mol formaldehyde and 2% of the azo dyestuif Azorubin S (Schultz VII,No. 212), liquor ratio 1:50. Wool flannel which contains about 20% nylonefiect threads is entered into the bath at 75. The bath is brought tothe boil within about 10 minutes and dyeing takes place for an hour atthe boil. A red wool dyeing is obtained with pure white effects.

A blue-red dyeing with pure white effects is obtained in the same waywith Amidonaphthol Red 6B dyestuff (Schultz VII, No. 110) on woolflannel which contains 20% Perlon U effect threads.

Example 15.Res'crved pol amide thread efiects in silk Bleached materialfrom unweighted silk which contains Perlon L effect threads reservedaccording to" Example 2 is dyed for an hour at 80- 100? in a bathcontaining 2% Erioglaucine A (Schultz; VII, No. 770), 4% acetic acid and10% Glaubers salt, liquor ratio 1:30. A pure blue dyeing with whiteeffect threads is obtained.

A red dyeing with white effects is obtained in the same manner on silkwith nylon effect threads reserved according to Example 1 with 2%Azorubin S (Schultz VII, No. 212).

Example 16.Cross dyeing of dyed and. reserved pol amide fibres to attainshot effects Nylon is dyed at the boil for an hour with 10% Glauberssalt calculated on the weight of the fibre, 3% formic acid and 2% of thechrome dyestuff from diazotised 6-nitro-4-'nethyl-2 aminophenol coupledwith 1-(4'-sulphopheny1)3- methyl-5-pyrazolone. It is then cooledsomewhat, and chromed for an hour at the boil with 2% sodium bichromateand 3% sulphuric acid. The nylon fibres which have been dyed ayellowish-red colour are then mordanted according to Example 1, and thenwoven into wool flannel ascffect threads. The wool flannel so preparedis then dyed according to Example 9 with 3% of the dyestuff fromdiazotised 6-nitro-4-methyl- 2-aminophenol coupled with1.8-dihydroxynaphthalene-3.6-disu1phonic acid and chromed with 1.5%sodium bichromate for an hour at the boil. Pure yellow-red effects areobtained on a deep blue background. Yellow-red effects on a blue-redbackground are obtained when dyeing is performed according to Example 5with 3% Amidonaphthol Red 63 (Schultz VII, No. 110).

What I claim is:

1. In a process for the dyeing, with a member selected from the classconsisting of acid and chrome dyestuffs, of mixed fabric made up ofnatural protein fibres and fibres prepared from synthetic polyamides ofthe linear type, the step of applying to the mixed fabric in a diluteaqueous acid medium about 3% by weight of the fibres of an acidcondensed resin from 1 mol of naphthalene monosulphonic acid, 0.7 to 1.5mols of a dihydroxydiphenyl sulphone and 0.7 to 1 mol of formaldehyde,said dilute aqueous acid medium having a concentration of up to about 5%by weight of the aqueous medium and being maintained at an elevateddyeing temperature, the acid in said aqueous acid mediumselected fromthe group consisting of formic acid and acetic acid, in order to reservesaid synthetic fibres.

2. In a process for the dyeing, with a member selected from the classconsisting of acid and chrome dyestuffs, of mixed fabric made up ofnatural protein fibres and fibres prepared from synthetic polyamides ofthe linear type, the step of treating the synthetic fibre component, before dyeing, in a dilute aqueous acid medium with about 3% by weight ofthe fibres of an acid condensed resin from 1 mol of naphthalenemonosulphonic acid, 0.7 to 1.5 mol's of a dihydroxydiphenyl sulphone and0.7 to 1 mol of formaldehyde, said dilute aqueous acid medium having aconcentration of up to about 5% by weight of the aqueous medium andbeing maintained at an elevated dyeing temperature, the acid in saidaqueous acid medium selected from the group consisting of formic acidand acetic acid, in order to reserve said synthetic fibres.

3. In a process for the dyeing, with a member selected from the classconsisting of acid and chrome dyestuffs, of mixed fabric made up ofnatural protein fibres and fibres prepared from synthetic polyamides ofthe linear type, the step of treating the said fabric, when dyeingin adilute aqueous acid medium with about 3% by weight of the fibres of anacid condensed resin from 1 mol of naphthalene monosulphonic acid, 0.7to 1.5 mols of a dihydroxydiphenyl sulphone and 0.7 to 1 mol offormaldehyde, said dilute aqueous acid medium having a concentration ofup to about 5% by weight of the aqueous medium and being maintained atan elevated dyeing temperature, the acid in said aqueous acid mediumselected from the group consisting of formic acid and acetic acid, inorder to reserve said synthetic fibres.

4. In a process for the dyeing, with a member selected from the classconsisting of acid and chrome dyestuffs, of mixed fabric made up of wooland fibres prepared from synthetic polyamides of the linear type, thestep of applying to the saidfabric in a. dilute aqueous acid mediumabout 3% by weight of the fibres of the acid condensed resin from 1 molof naphthalene monosulphonic acid, 1 mol of 4,4-dihydroxydiphenylsulphone and 1 mol of formaldehyde, said dilute aqueous acid mediumhaving a concentration of up to about 5% by weight of the aqueous mediumand being maintained at an elevated dyeing temperature, the acid in saidaqueous acid medium selected from the group consisting of formic acidand acetic acid, in order to reserve; said synthetic fibres.

OTTO FUCHS.

REFERENCE$ CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,668,144 Daimler May 1, 19281,901,536 Schafer Mar. 14, 1933 1,972,754 Biedermann Sept. 4, 19341,972,797 Schafer Sept. 4, 1934 2,204,512 Russellv June 11, 19402,242,681 Schafer May 11,.1941 2,282,264 Stiasny May 5, 1942 2,325,972Nusslein Aug. 3, 1943 2,533,100 Slugel Dec. 5, 1950 FOREIGN PATENTSNumber Country Date 337,887 Germany June 7, 1921 340,455 Germany Sept.10, 1921 552,015 Great Britain Mar. 19, 1943 639,326 France Mar. 6, 1928691,996 France July 28, 1930 OTHER REFERENCES American Dye Reporter forApril 21, 1947, page 223.

1. IN A PROCESS FOR THE DYEING, WITH A MEMBER SELECTED FROM THE CLASSCONSISTING OF ACID AND CHROME DYESTUFFS, OF MIXED FABRIC MADE UP OFNATURAL PROTEIN FIBRES AND FIBRES PREPARED FROM SYNTHETIC POLYAMIDES OFTHE LINEAR TYPE, THE STEP OF APPLYING TO THE MIXED FABRIC IN A DILUTEAQUEOUS ACID MEDIUM ABOUT 3% BY WEIGHT OF THE FIBRES OF AN ACIDCONDENSED RESIN FROM 1 MOL OF NAPHTHALENE MONOSULPHONIC ACID, 0.7 TO 1.5MOLS OF A DIHYDROXYDIPHENYL SULPHONE AND 0.7 TO 1 MOLD OF FORMALDEHYDE,SAID DILUTE AQUEOUS ACID MEDIUM HAVING A CONCENTRATION OF UP TO ABOUT 5%BY WEIGHT OF THE AQUEOUS MEDIUM AND BEING MAINTAINED AT AN ELEVATEDDYEING TEMPERATURE, THE ACID IN SAID AQUEOUS ACID MEDIUM SELECTED FROMTHE GROUP CONSISTING OF FORMIC ACID AND ACETIC ACID, IN ORDER TO RESERVESAID SYNTHETIC FIBRES.